have you seen chicago's river? >> it's pretty amazing, isn't it? >> yeah. >> it's really incredible. take a look at that video. september it just -- it's breathtaking. >> i guess this is a tradition of more than 50 years. >> they've been doing this for a long time. they use 40 pounds of vegetable dye, so in case you are concerned and wondering, oh, my gosh, is this terrible for fish and bad for the people? it's actually safe. it's a vegetable dye. they've been use it for many years. it's used to see if they can see leaks. >> it's actually pretty myself. kids must love it. it looks like it's glowing, doesn't it? >> it's very florescent. i mean, i wouldn't want to swim in it, safe or not. still kind of weird. >> yeah. >> there you go. nice tradition. >> well, guess what, it's not just in chicago. take a look. it's actually in tampa too. tampa turned its river green. see, i don't know. it's not especially pretty, but it's interesting. >> it's contagious, though. >> yeah, sure. nice way to celebrate. >> they use 70 pounds of vegetable dye in tampa, and